How to fix lighting inside a room
Eevee
For this of kind lightning you have to add Irradiance Volume object and under Render Properties &gt; Indirect Lightning &gt; Bake Indirect Lightning.

Notes:

your dimensions of object is huge (chair 40 m) ... you can select all and scale it down or go to Scene Properties &gt; Units and change it to something like 0.02 to result with something closer to reality
usually is used Sun light type (but I see it penetrates walls too much and I don't know how to avoid) always helps to ad Solidify modifier to walls
to avoid unwanted volumetric penetration change Render Properties &gt; Volumetrics &gt; Start to 4 End to 10, Distribution 0.8


Cycles
Same setup (irradiance is not used off course) ...

If you need brighter interior, there is more things you can try, but just increasing light Strength seems to be enough.